Help me find a fan

I think ive finally figured out what I want to do with my new grow area. I will have 3 tents, all 4x4. I will run 1000 watt in 2 of them, and a 400 watt in the 3rd (maybe upgraded to 1000 watt eventually). All of them have 6" cool tubes. I want to bring in air from outside to cool the lights, then exhaust that air into the attic.

I'm not sure where the incoming air will come from - any suggestions? I have 2 windows in the room, but one faces the street and the other faces my neighbor, and I still need to keep this stealth. May be suspicious sticking an air intake duct out the window. I could suck air from in the attic, then exhaust back into the attic, and that would probably be fine during cold weather, but in the summer when my attic is hot i'm not sure how effective this would be.

Regardless of where my fresh air intake is going to be I want to have the exhaust in the attic with a fan powerful enough to cool 3 1000 watt lights with 6" ducting, and overcome all the turns in the ducting. What type of fan and how many cfm would I need? Anyone willing to recommend specific models or anything would be very helpful. I don't mind dropping a few hundred on it if it will do the job I need effectively.

I was pretty impressed with these

750cfm should do you nicely id say 8" or 10 inch fan, that size fan you wont need intake, just go pasively from the room, maybe leave the window open a little if its not cold. vent into the attic as planned. be careful if it snows and your house is the only one without snow on the roof...... ya dig. if possible vent into the attic and into the chimney

I was going to have a passive intake, but I wanted the cool tube system separate from the actual grow room. My reasoning is that I can just run the fan 24/7 and put a dimmer on it to dial it back to what I need. In the winter when i'm sucking in zero degree air I would think I could tone it back and still remove all the heat, but in the summer when it's 90* outside I can run it full force and suck tons of air over the lights. I can also put in a window air conditioner and set it at a certain temperature and not worry about sucking my nice conditioned air over the cool tubes.

Will a 10" fan lose some of its effectiveness being rigged up to 6" ducting?

I would rather err on the side of having too much air flow rather than not enough. Especially since I can dial it down to what I need.

http://www.plantlightinghydroponics.com/valueline-12-inch-1060-cfm-centrifugal-inline-fan-p-2475.html

1060 cfm for $170.
12" centrifugal inline fan.

Will that work? If anyone has a different option let me know.

dude that thinfg will sound like a jet engine. i have an 8 inch rvk fan and its a faint hum in the next room through the wall its not exactly stealthy but it will 100% work

you should only need one line of airflow with a 10inch fan but theres no reason you cant have the cooltube line seperate, seems a little daft to have 2 fans running when one large would do.

i know ive recently been through this exact drama trying to find a solution to my grow stinking outside the house.

Since im placing it in the attic i'm not too concerned with the stealth factor. Not unusual at all to have a fan running in an attic. Though a jet engine would be pretty loud.

http://www.plantlightinghydroponics.com/valueline-inch-745-cfm-centrifugal-inline-fan-p-2261.html

$100 for a 745 cfm 8" centrifugal van or $190 for the vortex 8".

Much better choice vortex are a great brand what's the cfm rating?

The vortex is 747 cfm.

I'm thinking I should have the intake at the window. The two window choices are facing the street or facing the neighbor. Not sure how I could make it look like something suspicious wasnt going on. Even if I make a cover for the window to completely hide everything from the inside, people are going to wonder why my window is open in the winter.

any other options ? id say set it up vented up the chimney and see if you actually need the intake. i set mine up ad it draws passively from the room with the window and door shut

Chimney is on the other side of the house. No possible way to get there from this bedroom. I don't want to just go passively from my room for a couple reasons.

1. When it's cold outside I don't want 747 cf per minute of pre-warmed air being sucked from the rest of my house to displace the air being vented into the attic. I also think the cold outside air will be more effective, though I hope the volume will be enough to cool even with warm air (when the summer comes). Maybe this shouldn't be much of a concern, but it seems like a high powered fan running 24/7 sucking the air out of my house will increase my heating bill (I could deal with a reasonable increase, I just don't want a jump of a couple hundred dollars/mo).

2. In the summer it will be impossible to cool the room down while constantly venting the air. I think I will need a fresh air intake for the cool tubes, while leaving the air in the room so I can air condition it and get the room temp down. I think running the central air, or a window ac unit will be completely useless if I have a big van venting my air constantly.

central air will be useless in the summer. You will have to have a good window unit for that room alone to keep it cool.

My point was that either will be useless if i'm just venting the air to the attic.

wall mart...

do you have aany air bricks or vents ? i use an airbrick to vent out of my op. you could get one of those windows with a vent already in it and change it over but then the temp in winter might be a bit low.

I am changing plans slightly. Switching the grow room with my roommates room upstairs. Gonna come in from the attic on one side, and vent to the attic on the other side.

prob solved, happy growing man

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